This invention relates generally to circuits for suppressing transient noise pulses, and, more particularly, to such circuits that actually filter the supply by shorting out these pulses across the supply and decreasing the high frequency content of the noise pulse.
The presence of transient noise pulses or spikes resulting from lightning, line faults, or power switching can produce circuit-damaging overvoltages or erroneous, extraneous signals due to their high frequency content. Suppression circuits are known which are capable of substantially attenuating these transients, but these circuits are unable to entirely eliminate the disruptions.
Although a transient spike is attenuated, there remains a sharp or fast rise time and high frequency content that can produce one or more oscillations. In the low voltage, high frequency digital circuits in common use, the fluctuations can be falsely detected as data or control signals.